Webbing take-up device

ABSTRACT

A webbing take-up device includes a spool taking up webbing worn by an occupant, that is rotated in a pull-out direction by the webbing being pulled-out; a base lock that is provided capable of rotating integrally with the spool and restricts rotation of the spool in the pull-out direction in vehicle-emergency; a pawl that is rotated together with the spool and, by being displaced, engages with a winding ring and transmits rotation force of the spool to the winding ring, and a trigger ring including a restricting portion that is disposed in a restricting position at which displacement of the pawl is restricted in a state prior to the spool being rotated with respect to the base lock, and is disposed in a permitting position at which displacement of the pawl is permitted when the spool has been rotated in the pull-out direction with respect to the base lock.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority under 35 USC 119 from Japanese PatentApplication No. 2015-217711 filed Nov. 5, 2015, the disclosure of whichis incorporated by reference herein.

BACKGROUND

Field of the Invention

The present invention relates to a webbing take-up device.

Related Art

Japanese Patent Application Laid-Open (JP-A) Nos. 2012-12001 (PatentDocument 1) and 2015-120431 (Patent Document 2) describe webbing take-updevices in which rotation force of a spool is transmitted to a rotationforce transmitting member when a specific condition is met such as avehicle emergency or the like.

The webbing take-up device described in Patent Document 1 includes aplate section that is supported at the spool so as to be capable ofrotating relatively thereto, and a guide hole that engages with a pinformed to a second lock pawl is formed in the plate section. The secondlock pawl is rotated in a pull-out direction together with the spool,such that the pin of the second lock pawl moves along the guide holeformed in the plate section, and the second lock pawl engages with alock ring (rotation force transmitting member). Rotation force of thespool is thereby transmitted to the lock ring through the second lockpawl and so on. In the webbing take-up device described in PatentDocument 1, the circular column shaped pin needs to be provided to thesecond lock pawl, processing to form the guide hole in which the pin isengaged needs to be performed on the plate section, and a member thatcovers the second lock pawl need to be provided. Moreover, the pin ofthe second lock pawl needs to be inserted into the guide hole of theplate section in the assembly process of the webbing take-up device,such that the assembly process becomes complex.

The webbing take-up device described in Patent Document 2 includes alock base that is restricted from rotating in a vehicle emergency, and aguide groove, in which a guide shaft of a FL pawl is engaged, is formedin the lock base. The spool is rotated in the pull-out direction withrespect to the lock base, such that the guide shaft moves along theguide groove, and the FL pawl is moved toward a rotation radialdirection outside of the spool and engages with a lock ring (rotationforce transmitting member). Rotation force of the spool is therebytransmitted to the lock ring through the FL pawl and the like.

In webbing take-up devices configured such that rotation force of thespool is transmitted to the rotation force transmitting member when aspecific condition is met, it is essential that rotation force of thespool is suppressed from being transmitted to the rotation forcetransmitting member in a state in which the specific condition is notmet.

SUMMARY

In consideration of the above circumstances, a webbing take-up devicecapable of suppressing rotation force of a spool from being transmittedto a rotation force transmitting member in a case of transmitting beingnot required is obtained.

A webbing take-up device of a first aspect includes: a spool that takesup a webbing worn by an occupant, and that is rotated in a pull-outdirection due to the webbing being pulled out; a lock section that isconfigured to rotate (provided so as to be capable of rotating)integrally with the spool, and that is restricted from rotating in thepull-out direction in a vehicle emergency so as to limit rotation of thespool in the pull-out direction, with respect to the lock section; apawl that is rotated together with the spool and that, by beingdisplaced, engages with a rotation force transmitting member so as totransmit rotation force of the spool to the rotation force transmittingmember; and a restricting member that includes a restricting portion,wherein the restricting portion is disposed in a restricting positionbetween the pawl and the rotation force transmitting member, at whichdisplacement of the pawl is restricted, in a state prior to the spoolbeing rotated in the pull-out direction, with respect to the locksection, and the restricting portion is disposed in a permittingposition at which displacement of the pawl is permitted in a case inwhich the spool is rotated in the pull-out direction with respect to thelock section.

A webbing take-up device of a second aspect is the webbing take-updevice of the first aspect, wherein: a plurality of engagement toothportions with which the pawl is engaged are provided at the rotationforce transmitting member; and a dimension, in a rotationcircumferential direction of the spool, of an end of the restrictingportion, the end being disposed facing the plurality of engagement toothportions, exceeds a pitch between the plurality of engagement toothportions.

A webbing take-up device of a third aspect is the webbing take-up deviceof the first or the second aspect, wherein the restricting portionpresses the pawl in the state prior to the spool being rotated in thepull-out direction, with respect to the lock section.

A webbing take-up device of a fourth aspect is the webbing take-updevice of any one of the first to the third aspect, wherein therestricting member is configured including a stop portion that restrictsdisplacement of the restricting member in a rotation circumferentialdirection of the spool, with respect to the lock section, by beingstopped at a stopping portion formed at the lock section.

A webbing take-up device of a fifth aspect is the webbing take-up deviceof the fourth aspect, wherein: the restricting member is configuredincluding a facing portion, the facing portion being restricted frommoving in a rotation axis direction of the spool by being disposedbetween the lock section and the spool; and the stop portion extendsfrom the facing portion.

A webbing take-up device of a sixth aspect is the webbing take-up deviceof the fourth or the fifth aspect, wherein: the restricting member isconfigured including an abut portion that restricts displacement of therestricting member, with respect to the spool, by being abutted by anabutting portion provided at the spool in a case in which therestricting portion is disposed in the permitting position; and afterthe abut portion is abutted by the abutting portion, the stop portioncomes away from the stopping portion in a case in which the spool isrotated in the pull-out direction, with respect to the lock section.

A webbing take-up device of a seventh aspect is the webbing take-updevice of any one of the first to the sixth aspect, wherein: therestricting member is configured including a wound section that isattached to a ring shaped restricting member winding section provided atthe spool, the wound section being formed in a ring shape correspondingto the restricting member winding section, and the wound section beingformed in a plate shape with a thickness direction thereof being arotation radial direction of the spool.

A webbing take-up device of an eighth aspect is the webbing take-updevice of the seventh aspect, wherein: a first end portion on a pull-outdirection side of the wound section and a second end portion on anopposite side to the pull-out direction side of the wound sectionoverlap with each other; and the second end portion is disposed furthertoward an outer side in the rotation radial direction of the spool thanthe first end portion.

A webbing take-up device of a ninth aspect is the webbing take-up deviceof the seventh or the eighth aspect, wherein: the wound section isdisposed at an inner side in the rotation radial direction of the spoolwith respect to the rotation force transmitting member that has an innerperipheral portion formed in a ring shape; and a length from one sideend in the rotation circumferential direction of the spool to anotherside end in the rotation circumferential direction of the spool of thewound section is longer than an inner peripheral length in the rotationcircumferential direction of the spool of the rotation forcetransmitting member.

In the webbing take-up device of the first aspect, the webbing is pulledout from the spool, and the webbing is worn by an occupant. In a vehicleemergency, rotation of the lock section in the pull-out direction (thespool pull-out direction) is restricted, and rotation of the spool inthe pull-out direction is limited. When the occupant pulls the webbingfurther in the pull-out direction in a state in which rotation of thespool in the pull-out direction has been limited, the spool is rotatedin the pull-out direction with respect to the lock section. The webbingis thereby permitted to be pulled out from the spool.

In the webbing take-up device of the first aspect, the restrictingportion of the restricting member is changed (shifted) from a statepositioned in the restricting position to a state positioned in thepermitting position when the spool is rotated in the pull-out directionwith respect to the lock section. Thus, the restriction on displacementof the pawl by the restricting portion of the restricting member isreleased, and the pawl that is rotated together with the spool engageswith the rotation force transmitting member. Rotation force of the spoolis thereby transmitted to the rotation force transmitting member throughthe pawl.

Note that, in the webbing take-up device of the first aspect, therestricting portion of the restricting member restricts displacement ofthe pawl in the state prior to the spool being rotated with respect tothe lock section. Namely, the pawl does not engage with the rotationforce transmitting member in the state prior to the spool being rotatedwith respect to the lock section. Thus, the webbing take-up device ofthe first aspect enables rotation force of the spool to be suppressedfrom being transmitted to the rotation force transmitting member in acase of transmitting being not required.

In the webbing take-up device of the second aspect, the dimension, in arotation circumferential direction of the spool, of the end of therestricting portion of the restricting member, which is disposed facingthe plural engagement tooth portions provided at the rotation forcetransmitting member, is set at a dimension that exceeds a pitch betweenthe plural engagement tooth portions. This enables the end of therestricting portion of the restricting member to be suppressed fromunintentionally engaging with the plural engagement tooth portionsprovided at the rotation force transmitting member.

In the webbing take-up device of the third aspect, the restrictingportion of the restricting member presses the pawl in the state prior tothe spool being rotated with respect to the lock section. This enablesthe pawl that rotates together with the spool to be suppressed fromvibrating when the webbing is pulled out from the spool, and when thewebbing is taken up onto the spool.

In the webbing take-up device of the fourth aspect, displacement of therestricting member in the rotation circumferential direction (the spoolrotation circumferential direction) with respect to the lock section isrestricted by the stop portion of the restricting member being stoppedby the stopping portion of the lock section. This enables therestricting portion of the restricting member to be shifted (disposed)from the restricting position to the permitting position by rotating thespool in the pull-out direction with respect to the lock section,without separately providing a mechanism that shifts (disposes) therestricting portion of the restricting member from the restrictingposition to the permitting position.

In the webbing take-up device of the fifth aspect, movement of thefacing portion of the restricting member in the rotation axis direction(the spool rotation axis direction) is restricted by the spool and thelock section. Forming the stop portion so as to extend from the facingportion enables the stop portion of the restricting member to besuppressed from unexpectedly coming away from the stopping portion ofthe lock section.

In the webbing take-up device of the sixth aspect, the abut portion ofthe restricting member is abutted by the abutting portion of the spoolwhen the spool is rotated in the pull-out direction with respect to thelock section and the restricting portion of the restricting member isshifted (disposed) from the restricting position to the permittingposition. The stop portion of the restricting member comes away from thestopping portion of the lock section when the spool is rotated in thepull-out direction with respect to the lock section after the abutportion of the restricting member is abutted by the abutting portion ofthe spool. This enables limitation on rotation of the spool in thepull-out direction with respect to the lock section by the restrictingmember to be suppressed. Namely, this enables pull-out load of thewebbing from the spool to be suppressed from becoming unintentionalload.

In the webbing take-up device of the seventh aspect, the wound sectionof the restricting member is attached to the restricting member windingsection of the spool, and the wound section of the restricting member isformed in a plate shape with its thickness direction being the rotationradial direction (the spool rotation radial direction). This enables thewound section of the restricting member to be suppressed from projectingout toward the rotation radial direction outside with respect to therestricting member winding section of the spool. This enables anincrease in the size of the body of the webbing take-up device to besuppressed.

In the webbing take-up device of the eighth aspect, the second endportion is disposed further toward outside in the rotation radialdirection of the spool than the first end portion. Thus, even though thewound section of the restricting member has expanded in diameter whenthe spool is rotated in the pull-out direction, the first end portionwhich is on the pull-out direction side of the wound section of therestricting member can be suppressed from catching on a member disposedat the radial direction outside of the wound section.

In the webbing take-up device of the ninth aspect, the wound section ofthe restricting member is disposed on the spool rotation radialdirection inside with respect to the rotation force transmitting member,further, the length (a dimension in the spool rotation circumferentialdirection) of the wound section of the restricting member is set longerthan the inner peripheral length (a dimension in the spool rotationcircumferential direction) of the rotation force transmitting member.Thus, even though the wound section of the restricting member hasexpanded in diameter when the spool is rotated in the pull-outdirection, the first end portion on the pull-out direction side of thewound section of the restricting member can be suppressed from catchingon an inner peripheral portion of the rotation force transmittingmember. This enables rotation force of the spool to be prevented frombeing transmitted to the rotation force transmitting member through therestricting member.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments will be described in detail with reference to thefollowing figures, wherein:

FIG. 1 is an exploded perspective view illustrating a webbing take-updevice of an exemplary embodiment;

FIG. 2 is an exploded perspective view illustrating a spool assemblybody;

FIG. 3 is an exploded perspective view illustrating a force limiter loadgenerating and adjusting mechanism of a webbing take-up device;

FIG. 4 is a face-on view illustrating a force limiter load generatingand adjusting mechanism;

FIG. 5 is a face-on view illustrating a cam turning mechanism;

FIG. 6 is an enlarged face-on view illustrating a cam, a lever, and soon when webbing is worn by an occupant with a large build;

FIG. 7 is an enlarged face-on view illustrating a cam, a lever, and soon when webbing is worn by an occupant with a small build;

FIG. 8 is a side view schematically illustrating a state prior to anenergy absorbing wire being taken up by a winding ring;

FIG. 9 is a side view schematically illustrating a state in which awinding ring is taking up an energy absorbing wire;

FIG. 10 is an enlarged perspective view illustrating a location of aspool assembly body provided with a rotation force transmittingmechanism, illustrating a state in which a restricting portion of atrigger ring is disposed in a restricting position and a pawl isdisposed in a housed position;

FIG. 11 is an enlarged perspective view corresponding to FIG. 10,illustrating a location of a spool assembly body provided with arotation force transmitting mechanism, and illustrating a state in whicha restricting portion of a trigger ring is disposed in a permittingposition and a pawl is disposed in an engaged position;

FIG. 12 is a plan view illustrating a trigger ring;

FIG. 13 is an explanatory view for explaining operation of a rotationforce transmitting mechanism, illustrating a state prior to a spoolbeing rotated with respect to a lock base;

FIG. 14 is an explanatory view corresponding to FIG. 13 for explainingoperation of a rotation force transmitting mechanism, illustrating astate when a spool has started to be rotated with respect to a lockbase;

FIG. 15 is an explanatory view corresponding to FIG. 13 and so on forexplaining operation of a rotation force transmitting mechanism,illustrating a state in which a pawl abuts a pawl abut portion of atrigger ring;

FIG. 16 is an explanatory view corresponding to FIG. 13 and so on forexplaining operation of a rotation force transmitting mechanism,illustrating a process in which a pawl is moving toward an engagedposition side;

FIG. 17 is an explanatory view corresponding to FIG. 13 and so on forexplaining operation of a rotation force transmitting mechanism,illustrating a state in which a pawl is disposed in an engaged position;

FIG. 18A is a plan view illustrating a rotation force transmittingmechanism according to a second exemplary embodiment; FIG. 18B is a topview of the rotation force transmitting mechanism illustrated in FIG.18A; FIG. 18C is a left side view of the rotation force transmittingmechanism illustrated in FIG. 18A; FIG. 18D is a bottom view of therotation force transmitting mechanism illustrated in FIG. 18A, and FIG.18E is a right side view of the rotation force transmitting mechanismillustrated in FIG. 18A;

FIG. 19 is an exploded perspective view illustrating a rotation forcetransmitting mechanism according to a third exemplary embodiment;

FIG. 20 is an enlarged perspective view illustrating a rotation forcetransmitting mechanism according to the third exemplary embodiment,illustrating a state in which a restricting portion of a trigger ring isdisposed in a restricting position and a pawl is disposed in a housedposition;

FIG. 21 is an enlarged perspective view corresponding to FIG. 20,illustrating a rotation force transmitting mechanism according to thethird exemplary embodiment, and illustrating a state in which arestricting portion of a trigger ring is deformed and disposed in apermitting position and a pawl is disposed in an engaged position;

FIG. 22 is an exploded perspective view illustrating a rotation forcetransmitting mechanism according to a fourth exemplary embodiment; and

FIG. 23 is an explanatory view for explaining operation of a rotationforce transmitting mechanism according to the fourth exemplaryembodiment.

DETAILED DESCRIPTION

Explanation follows regarding a webbing take-up device according to anexemplary embodiment, with reference to FIG. 1 to FIG. 17. Note that thearrow Z direction, the arrow R direction, and the arrow C directionindicated in the drawings respectively indicate a rotation axisdirection (axis direction of rotation), a rotation radial direction(radial direction of rotation), and a rotation circumferential direction(circumferential direction of rotation) of a spool, as appropriate.Unless specifically stated otherwise, simple reference to the axialdirection, radial direction, and circumferential direction below refersto the rotation axis direction, the rotation radial direction, and therotation circumferential direction of the spool.

As illustrated in FIG. 1, a webbing take-up device 10 according to anexemplary embodiment includes a frame 12, a spool 14 that takes upwebbing 100, and a torsion shaft 18 configuring a first force limitermechanism 16 (see FIG. 2 also). The webbing take-up device 10 alsoincludes a pre-tensioner mechanism 20 that forcibly rotates the spool 14in a take-up direction in a vehicle emergency, and a second forcelimiter mechanism 22 that includes a force limiter load generatingmechanism and a force limiter load adjusting mechanism.

The frame 12 is formed in a rectangular frame shape, and includes aplate shaped back plate 12A that is fixed to the vehicle body. Legpieces 12B, 12C extend out at substantially right angles from both widthdirection end portions of the back plate 12A. End portions of the legpieces 12B, 12C at the opposite side to the back plate 12A are linkedtogether by a connecting plate 12D.

A spool assembly body 80 is illustrated in FIG. 2. As illustrated inFIG. 2, the spool assembly body 80 includes the spool 14 on which thewebbing 100 worn by an occupant is taken up. The spool assembly body 80also includes a rotation force transmitting mechanism 82 provided to anend portion on one axial direction side of the spool 14, a base lock 30serving as a lock section provided to the spool 14 so as to be capableof rotating integrally thereto, and the torsion shaft 18 that joins(links) the spool 14 and the base lock 30 together.

The spool 14 is formed in a substantially circular column shape andincludes a take-up section 14A on which the webbing 100 is taken up. Aninsertion hole 14B for inserting the webbing 100 is formed in thetake-up section 14A. The insertion hole 14B is formed in a rectangularshape with its length direction along the axial direction as viewed fromthe radial direction outside. The webbing 100 is inserted through theinsertion hole 14B and a stopper member is attached to a lengthdirection end portion of the webbing 100, thereby anchoring the lengthdirection end portion of the webbing 100 to the spool 14. The spool 14is rotated toward another side in the circumferential direction (theopposite direction to the arrow C direction), namely, the spool 14 isrotated in the take-up direction, to take up the webbing 100 onto thespool 14. The spool 14 is rotated toward one side in the circumferentialdirection (the arrow C direction), namely, the spool 14 is rotated in apull-out direction, by pulling the webbing 100 out from the spool 14.

An end portion on another side in the axial direction (the oppositedirection to the arrow Z direction) of the spool 14 configures anon-illustrated rotation force transmitting section that transmitsrotation force of a pinion gear 88 (see FIG. 1) configuring part of thepre-tensioner mechanism 20, described later, through a one-way clutch84. The one-way clutch 84 is configured so as to only transmit rotationforce in the take-up direction of the pinion gear 88 to the spool 14.

A torsion shaft insertion hole 14D for inserting the torsion shaft 18,described later, is formed in an axial center portion of the spool 14. Anon-illustrated first engage portion, for engaging a first serratedportion 18B formed on the torsion shaft 18, is formed on the anotherside in the axial direction of the torsion shaft insertion hole 14D. Thefirst serrated portion 18B of the torsion shaft 18 engages with thefirst engage portion, such that the torsion shaft 18 and the spool 14are joined together so as to be capable of rotating integrally to eachother.

The base lock 30 and a lock gear 32, configuring part of a lockmechanism, are provided on the one side in the axial direction of thespool 14. The base lock 30 is formed in a substantially circular plateshape with its thickness direction along the axial direction. The lockgear 32 is supported by the base lock 30 so as to be capable of tilting(swinging). In a vehicle emergency, the base lock 30 and the lock gear32 engage with non-illustrated ratchet teeth provided to the leg piece12C of the frame 12 (see FIG. 1), thereby restricting rotation of thebase lock 30 in the pull-out direction.

A second engage portion 30A, for engaging a second serrated portion 18Cformed on the torsion shaft 18, described below, is formed in an axialcenter portion of the base lock 30. The second serrated portion 18C ofthe torsion shaft 18 engages with the second engage portion 30A, suchthat the torsion shaft 18 and the base lock 30 are joined together so asto be capable of rotating integrally to each other.

The torsion shaft 18 is formed in substantially a rod shape. The firstserrated portion 18B and the second serrated portion 18C, which arerespectively engaged by the first engaging portion provided to the spool14 and the second engage portion 30A provided to the base lock 30, arerespectively formed at an intermediate portion, and an end portion onone side, in the axial direction of the torsion shaft 18. A location ofthe torsion shaft 18 between the first serrated portion 18B and thesecond serrated portion 18C configures a twisting portion 18A that has asmaller diameter than the first serrated portion 18B and the secondserrated portion 18C, and that has a substantially constant circularcross-section profile along the axial direction. When load acting on theoccupant from the webbing 100 has exceeded a specific value in a statein which rotation of the spool 14 in the pull-out direction with respectto the base lock 30 has been limited through the torsion shaft 18, thetwisting portion 18A of the torsion shaft 18 is twisted, and rotation ofthe spool 14 in the pull-out direction with respect to the base lock 30is permitted. A location on the another side in the axial direction ofthe torsion shaft 18 configures an engagement shaft portion 18D that isinserted through a non-illustrated through-hole formed in the endportion on the another axial direction side of the spool 14, and thatengages with a non-illustrated return spring or the like. Note that thetorsion shaft 18 does not fall out of the torsion shaft insertion hole14D formed in the spool, due to a stopper member 86 being attached tothe engagement shaft portion 18D.

As illustrated in FIG. 1, the pre-tensioner mechanism 20 is configuredincluding a cylinder 36 connected to a case 34, a non-illustrated rackdisposed inside the cylinder 36, the pinion gear 88 that meshes with themoving rack, and a gas generator 42 that is attached to one end portionof the cylinder 36. The pressure inside the cylinder 36 rises due tohigh pressure gas generated on actuating the gas generator 42, such thatthe rack is moved, and the rack and the pinion gear 88 meshing with therack is rotated in the take-up direction. The spool 14 is therebyrotated in the take-up direction.

As illustrated in FIG. 3, the second force limiter mechanism 22 includesa housing 44 that is fixed to the leg piece 12C of the frame 12 (seeFIG. 1), and a cover sheet 46 that is attached to an end portion on theone side in the axial direction of the housing 44. The second forcelimiter mechanism 22 also includes a winding ring 48, an energyabsorbing wire 50, a wire guide 52, a lever 54, and a cam 56 that aredisposed between the housing 44 and the cover sheet 46.

The housing 44 is formed in a box shape open toward the one side in theaxial direction. The housing 44 includes a bottom wall 44A that extendsso as to face the leg piece 12C of the frame 12 (see FIG. 1), and a sidewall 44B that bends and extends from an outer peripheral end of thebottom wall 44A toward the one side in the axial direction. An insertionhole 44C for inserting the end portion on the one side in the axialdirection of the spool 14 (see FIG. 1) is formed in the bottom wall 44A.The winding ring 48, described later, is supported so as to be capableof rotating by engaging with a stepped portion 44D formed at an innerperipheral edge portion of the insertion hole 44C. A wire guideattachment portion 44E, to which the wire guide 52, described later, isattached, is provided at the radial direction outside of a location ofthe bottom wall 44A where the insertion hole 44C is formed. A circularshaped support hole 44F is formed in the wire guide attachment portion44E. A radial direction inside face of the side wall 44B is disposedfacing the winding ring 48, described later, in the radial direction.Part of the radial direction inside face of the side wall 44B configuresa preset face 44G formed in a circular tube faced shape. A recess shapedlever support portion 44H, which supports the lever 54, described later,so as to allow tilting (swinging), is formed in a location of the sidewall 44B corresponding to the wire guide attachment portion 44E of thebottom wall 44A. A recess shaped cam placement portion 44I, in which thecam 56, described later, is disposed, is formed in a location of theside wall 44B corresponding to the wire guide attachment portion 44E ofthe bottom wall 44A, this also being a location adjacent to the leversupport portion 44H. Note that a non-illustrated shaft support hole thatsupports an end portion on the another side in the axial direction ofthe cam 56, described later, is formed in a location of the bottom wall44A corresponding to the cam placement portion 44I.

The cover sheet 46 is attached to an end portion on the one side in theaxial direction of the side wall 44B of the housing 44. An insertionhole 46A, which corresponds to the insertion hole 44C formed in thebottom wall 44A of the housing 44, is formed in the cover sheet 46.Circular shaped support holes 46B are formed in locations of the coversheet 46 facing the wire guide attachment portion 44E of the housing 44in the axial direction. An insertion hole 46C, through which a shaftportion 56A of the cam 56, described later, is inserted, is formed in alocation of the cover sheet 46 corresponding to the cam placementportion 44I of the housing 44.

The winding ring 48, which serves as a rotation force transmittingmember, is formed in a tube shape. The winding ring 48 is disposedcoaxially to the spool 14, and at the radial direction outside of theend portion on the one side in the axial direction of the spool 14 (thelocation where the rotation force transmitting mechanism 82 (see FIG.1), described later, is provided). Plural engagement tooth portions 48Athat engage a pawl 92, described later, are formed around thecircumferential direction on an inner peripheral portion of the windingring 48. As illustrated in FIG. 3, FIG. 8, and FIG. 9, a flange portion48B that projects out toward the radial direction outside is formed atan end portion on the another side in the axial direction of an outerperipheral portion of the winding ring 48. A location on the outerperipheral face of the winding ring 48, that is further toward the oneside in the axial direction than the flange portion 48B, configures atake-up face 48C for taking up the energy absorbing wire 50, describedbelow.

The energy absorbing wire 50 is formed by winding a linear member (awire shaped member) formed using steel material or the like.Specifically, the energy absorbing wire 50 includes a ring shapedportion 50A formed by winding the linear member in ring shape around thecircumferential direction such that ring-like portions are arrangedalong the axial direction. The external diameter of the ring shapedportion 50A, in a natural state, prior to being set on the preset face44G of the housing 44 described above, is an external diameter that islarger than an inner diameter of the preset face 44G. The ring shapedportion 50A is disposed at the radial direction inside of the presetface 44G in a state in which the ring shaped portion 50A has beenreduced in diameter, and a radial direction outside face of the ringshaped portion 50A abuts a radial direction inside face of the presetface 44G, thereby attaching the energy absorbing wire 50 to the housing44. An end portion 50B on the one side in the axial direction of theenergy absorbing wire 50 configures part of the ring shaped portion 50A.As illustrated in FIG. 4, an end portion 50C on the another side in theaxial direction of the energy absorbing wire 50 is displaced to the oneside in the axial direction of the ring shaped portion 50A through theradial direction inside of the ring shaped portion 50A. The end portion50C on the another side in the axial direction of the energy absorbingwire 50 is anchored to an end portion on the one side in the axialdirection of the winding ring 48. Thus, as illustrated in FIG. 8, alocation 50D of the energy absorbing wire 50 that is anchored to thewinding ring 48, and a location 50E of the energy absorbing wire 50 thatis sandwiched (held) between the wire guide 52, described later, and thelever 54, are disposed offset from each other in the axial direction ofthe winding ring 48.

As illustrated in FIG. 3 and FIG. 4, the wire guide 52 is formed using amaterial that has a lower strength than the energy absorbing wire 50. Aradial direction outside face and a radial direction inside face of thewire guide 52 are formed in gently curved such as crescent shape asviewed from the axial direction, and the wire guide 52 is formed in ablock shape with a specific thickness in the axial direction. Circularcolumn shaped support columns 52A and 52B, which are respectivelyinserted into the support hole 44F formed in the housing 44 and thesupport holes 46B formed in the cover sheet 46, are respectivelyprovided on the another side in the axial direction and the one side inthe axial direction of the wire guide 52. The radial direction insideface of the wire guide 52 configures a set face 52C that is abutted bythe ring shaped portion 50A of the energy absorbing wire 50 attached tothe housing 44. In a state in which the wire guide 52 has been attachedto the wire guide attachment portion 44E of the housing 44, the set face52C is disposed along an extension (imaginary extension) of the presetface 44G. Note that the curvature of the set face 52C and the curvatureof the preset face 44G are set so as to be substantially the samecurvature as each other. The radial direction outside face of the wireguide 52 configures a guide face 52D that guides a location between theend portion 50C on the another side in the axial direction of the energyabsorbing wire 50 and a location that has been displaced from the ringshaped portion 50A of the energy absorbing wire 50. An indented portion52E is formed in a circumferential direction intermediate portion of theguide face 52D. Plural curved portions are thereby formed on the guideface 52D.

The lever 54 is formed in a block shape including a shaft portion 54Adisposed inside the lever support portion 44H formed in the housing 44,an arm portion 54B extending from the shaft portion 54A toward the wireguide 52 side, and a movement portion 54C provided at a leading end ofthe arm portion 54B. Specifically, the shaft portion 54A is formed in acircular column shape corresponding to the shape of an inner peripheralface of the lever support portion 44H. The shaft portion 54A is disposedinside the lever support portion 44H, thereby tilting (swinging) the armportion 54B. Swinging the arm portion 54B moves the movement portion 54Cprovided at the leading end of the arm portion 54B in a directiontoward, or away from, the wire guide 52. The movement portion 54C isdisposed facing the indented portion 52E formed in the guide face 52D ofthe wire guide 52. By moving the movement portion 54C toward the wireguide 52 side, the energy absorbing wire 50 is sandwiched (such asclamped) between the movement portion 54C and the wire guide 52 and isdeformed in a shape running along the guide face 52D of the wire guide52.

The cam 56 includes the shaft portion 56A formed in a substantiallycircular column shape, and a cam body portion 56B that is provided onanother side in the axial direction of the shaft portion 56A and that,by being rotated, presses the movement portion 54C of the lever 54. Asillustrated in FIG. 4, the cam body portion 56B is formed in a partiallycutout circular column shape. A large diameter portion 56C, a smalldiameter portion 56D set with a smaller radius of curvature than thelarge diameter portion 56C, and a connecting portion 56E that connectsthe large diameter portion 56C and the small diameter portion 56Dtogether, are thereby provided at an outer peripheral portion of the cambody portion 56B. In a state in which the large diameter portion 56C ofthe cam body portion 56B and the movement portion 54C of the lever 54abut each other, the movement portion 54C of the lever 54 is disposedclose to the guide face 52D of the wire guide 52. In a state in whichthe small diameter portion 56D of the cam body portion 56B and themovement portion 54C of the lever 54 abut each other, the movementportion 54C of the lever 54 is disposed separated from the guide face52D of the wire guide 52.

As illustrated in FIG. 5, the cam 56 is rotated at a reduced speed by acam rotating (turning) mechanism 58. Specifically, the cam turningmechanism 58 is configured including a primary gear 60 that is attachedto an end portion on the one side in the axial direction of the torsionshaft 18 so as to be capable of rotating integrally with the spool 14, afinal gear 62 that is attached to an end portion on the one side in theaxial direction of the cam 56, and a first intermediate gear 64 and asecond intermediate gear 66 that transmit rotation of the primary gear60 to the final gear 62. As illustrated in FIG. 7, the small diameterportion 56D of the cam body portion 56B and the movement portion 54C ofthe lever 54 abut each other when a specific length of the webbing 100has been pulled from the spool 14 from a state in which the webbing 100is fully wound on the spool 14. Thus, the movement portion 54C of thelever 54 is disposed separated from the guide face 52D of the wire guide52. As illustrated in FIG. 6, after the connecting portion 56E of thecam body portion 56B and the movement portion 54C of the lever 54 haveabutted each other, the large diameter portion 56C of the cam bodyportion 56B and the movement portion 54C of the lever 54 abut eachother, when the webbing 100 has been pulled out from the spool 14 beyondthe above mentioned specific length. The movement portion 54C of thelever 54 is thereby disposed close to the guide face 52D of the wireguide 52. Note that in the present exemplary embodiment, setting isperformed such that the amount of webbing 100 pulled out from the spool14 does not exceed the above mentioned specific length when the webbing100 is worn by an occupant with a small build, and such that the amountof webbing 100 pulled out from the spool 14 exceeds the above mentionedspecific length when the webbing 100 is worn by an occupant with a largebuild. Note that an occupant with a small build is an occupant with asimilar physique to an AF05 dummy, and an occupant with a large build isan occupant with a similar physique to an AM50 dummy. As illustrated inFIG. 5, in the present exemplary embodiment, the primary gear 60, thefinal gear 62, the first intermediate gear 64, and the secondintermediate gear 66 configuring the cam turning mechanism 58 aredisposed inside a gear housing recessed section 68A formed in a gearcase 68 attached to the leg piece 12C of the frame 12. The gear housingrecessed section 68A is closed off by a gear cover 70 (see FIG. 1).

Explanation follows regarding the rotation force transmitting mechanism82, this being a relevant (main) portion of the present exemplaryembodiment.

As illustrated in FIG. 10 and FIG. 11, the rotation force transmittingmechanism 82 transmits rotation force of the spool 14 to the windingring 48 previously described (see FIG. 3). The rotation forcetransmitting mechanism 82 is configured including a pawl housing section90 provided at the end portion on the one axial direction side of thespool 14, the pawl 92 that is housed inside the pawl housing section 90,and a trigger ring 94 serving as a restricting member and a pawldisplacement member attached to an outer peripheral portion of the pawlhousing section 90.

As illustrated in FIG. 2, the pawl housing section 90 is providedadjacent to the take-up section 14A at which the webbing 100 is takenup. The outer peripheral face of the pawl housing section 90 configuresa trigger ring attachment section 90A serving as a restricting memberwinding section and a pawl displacement member winding section. A pairof flanges 90B are formed at the trigger ring attachment section 90A,projecting out toward the radial direction outside on the one side andthe another side in the axial direction of the trigger ring attachmentsection 90A. The height (dimension in the radial direction) of theflanges 90B with respect to the trigger ring attachment section 90A isset with a higher dimension than the thickness of the trigger ring 94,described below. A pawl housing hole 90C that is open toward the radialdirection outside is formed in the pawl housing section 90. An endportion on the radial direction inside and another side in thecircumferential direction of the pawl housing hole 90C configures asupport portion 90D that supports the pawl 92 so as to allow moving withtilt manner (swinging) (see FIG. 13 also). A connectingportion-placement recessed portion 90E, disposed such that a connectingportion 94H of the trigger ring 94, described later, is capable ofmoving in the circumferential direction, is formed in an outerperipheral portion of an end portion on the one side in the axialdirection of the pawl housing section 90. Part of an edge on the anotherside in the circumferential direction of the connectingportion-placement recessed portion 90E configures an abutting portion90F to which the connecting portion 94H is abutted.

As illustrated in FIG. 13, the pawl 92 is disposed inside the pawlhousing hole 90C formed in the pawl housing section 90 of the spool 14.An end portion on one side in the length direction of the pawl 92configures a supported portion 92A that is supported by the supportportion 90D provided inside the pawl housing hole 90C. Two engagementteeth 92B, disposed adjacent to each other along the circumferentialdirection, are provided at an end portion on another side in the lengthdirection of the pawl 92. The engagement tooth 92B on the another sidein the circumferential direction is referred to as a main engagementtooth 92B (G1), and the engagement tooth 92B disposed on the one side inthe circumferential direction is referred to as an auxiliary engagementtooth 92B (G2). A raised portion 92C formed in a shape protruding towardthe radial direction outside is formed at a location at the radialdirection outside of a length direction intermediate portion of the pawl92. A leg portion 92D is formed in a shape protruding toward the radialdirection inside at a location on the radial direction inside of thelength direction intermediate portion of the pawl 92. An indentation(recessed portion) 92E that is open toward the radial direction insideis formed between the leg portion 92D and the auxiliary engagement tooth92B (G2) of the pawl 92. Note that a state in which the pawl 92 hasswung furthest in the arrow Y1 direction about the support portion 90Dis referred to as a state in which the pawl 92 is positioned in a housedposition K1. In the present exemplary embodiment, the depth of the pawlhousing section 90 (the depth of the pawl housing section 90 in thelength direction of the pawl 92 in the state in which the pawl 92 ispositioned in the housed position K1) is set shallower (smaller) than adimension of the pawl 92 in the length direction. Thus, in the state inwhich the pawl 92 is positioned in the housed position K1, a tooth tipof the main engagement tooth 92B (G1) is positioned slightly furthertoward the radial direction outside than the trigger ring attachmentsection 90A. As illustrated in FIG. 17, a state in which the pawl 92 hasbeen swung in the arrow Y2 direction, which is a direction opposite tothe arrow Y2 direction, about the support portion 90D, and theengagement teeth 92B of the pawl 92 are capable of engaging with theengagement tooth portions 48A of the winding ring 48, is referred to asa state in which the pawl 92 is positioned in an engaged position K2. Inthe state in which the pawl 92 is positioned in the engaged position K2,the main engagement tooth 92B (G1) and the auxiliary engagement tooth92B (G2) of the pawl 92 are positioned further toward the radialdirection outside than the trigger ring attachment section 90A.

As illustrated in FIG. 2 and FIG. 12, the trigger ring 94 is formed bybending and the like a single plate shaped member, for example, formedby punching a metal plate such as steel plate into a specific shape.Specifically, the trigger ring 94 is formed in a ring shape and includesa wound section 94A extending with its thickness direction being in theradial direction. In the present exemplary embodiment, a dimension(length in the circumferential direction) from an end 94B on the oneside in the circumferential direction to an end 94C on the another sidein the circumferential direction of the wound section 94A is set longerthan an inner peripheral length in the circumferential direction (acircumferential length of a circle passing through tooth tips of theengagement tooth portions 48A in axial direction view) of the windingring 48 (see FIG. 3). In addition thereto, in the present exemplaryembodiment, an end portion 94D (first end portion) on the one side inthe circumferential direction and an end portion 94E (second endportion) on the another side in the circumferential direction of thewound section 94A overlap each other, and the end portion 94E on theanother circumferential direction side of the wound section 94A isdisposed further toward the radial direction outside than the endportion 94D on the one circumferential direction side. An internaldiameter D1 of the wound section 94A in a state prior to the woundsection 94A being attached to the trigger ring attachment section 90A ofthe pawl housing section 90 is set smaller than an external diameter D2(see FIG. 13) of the trigger ring attachment section 90A. The woundsection 94A is wound onto and retained by the trigger ring attachmentsection 90A by spring force occurring in the trigger ring 94 (the woundsection 94A) due to the internal diameter of the wound section 94A beingexpanded so as to correspond to the external diameter D2 of the triggerring attachment section 90A.

As illustrated in FIG. 13, in a state in which the wound section 94A hasbeen wound onto the trigger ring attachment section 90A and further in astate in which the spool assembly body 80 has been assembled, part ofthe wound section 94A covers the main engagement tooth 92B (G1) and theauxiliary engagement tooth 92B (G2) of the pawl 92 from the radialdirection outside, and presses the tooth tip of the main engagementtooth 92B (G1) toward the radial direction inside. Note that the part ofthe wound section 94A that covers the main engagement tooth 92B (G1) andthe auxiliary engagement tooth 92B (G2) of the pawl 92 from the radialdirection outside is referred to as a restricting portion 94F. A statein which the restricting portion 94F is disposed in a position coveringthe main engagement tooth 92B (G1) and the auxiliary engagement tooth92B (G2) is referred to as a state in which the restricting portion 94Fis disposed in a restricting position B1. As illustrated in FIG. 10 andFIG. 11, an end T1 (an end on the another side in the axial direction)of the restricting portion 94F that is disposed facing the pluralengagement tooth portions 48A of the winding ring 48 in the radialdirection is inclined (curved) toward the one side in the axialdirection on progression toward the one side in the circumferentialdirection. Note that, as illustrated in FIG. 13, a circumferencedimension in the circumferential direction of the inclined (curved) endT1 of the restricting portion 94F that is disposed facing the pluralengagement tooth portions 48A of the winding ring 48 in the radialdirection is set to a dimension that exceeds the pitch between theplural engagement tooth portions 48A of the winding ring 48. Namely, thecircumference dimension is set that exceeds a spacing in thecircumferential direction between a tooth tip 48D of one engagementtooth portion 48A and a tooth tip 48D of another engagement toothportion 48A disposed adjacent to the one engagement tooth portion 48A inthe circumferential direction.

As illustrated in FIG. 15 to FIG. 17, when the spool 14 is rotatedtoward the one side in the circumferential direction with respect to thetrigger ring 94 (when the trigger ring 94 is displaced toward theanother side in the circumferential direction with respect to the spool14), the restricting portion 94F is disposed in a position that does notcover the main engagement tooth 92B (G1) or the auxiliary engagementtooth 92B (G2). Note that a state in which the restricting portion 94Fis disposed in a position that does not cover the main engagement tooth92B (G1) or the auxiliary engagement tooth 92B (G2) is referred to as astate in which the restricting portion 94F is disposed in a permittingposition B2. Disposing the restricting portion 94F in the permittingposition B2 permits the pawl 92 to be swung toward the arrow Y2direction side.

As illustrated in FIG. 2 and FIG. 12, the trigger ring 94 includes apawl abut portion 94G that extends out from a location which is on theanother side in the axial direction of the wound section 94A toward theinside of the pawl housing hole 90C formed in the pawl housing section90 (toward the radial direction inside), and that is disposed on the oneside in the circumferential direction with respect to the pawl 92provided inside the pawl housing hole 90C. The pawl abut portion 94G isinclined toward the another side in the circumferential direction andtoward the radial direction inside in axial direction view. Asillustrated in FIG. 17, the pawl abut portion 94G is capable ofdeforming toward the opposite side to the pawl 92 when abutted by thepawl 92, and also capable of returning toward the pawl 92 side from thedeformed state.

As illustrated in FIG. 2 and FIG. 12, the trigger ring 94 includes theconnecting portion 94H, serving as a facing portion and an abut portion,extending from an end on the one side in the axial direction of thewound section 94A toward the radial direction inside. The connectingportion 94H extends with its thickness direction being the axialdirection. The connecting portion 94H is configured including a firstextension portion E1 formed in a substantially rectangular shape inaxial direction view, and a second extension portion E2 extending fromthe radial direction inside portion of the first extension portion E1toward the another side in the circumferential direction. The connectingportion 94H explained above is disposed inside the connectingportion-placement recessed portion 90E formed in the pawl housingsection 90, thereby limiting a displacement amount (rotation (turn)angle) of the trigger ring 94 with respect to the spool. The connectingportion 94H is disposed between the connecting portion-placementrecessed portion 90E formed in the pawl housing section 90 and the baselock 30, such that movement of the connecting portion 94H in the axialdirection is restricted.

Further, the trigger ring 94 includes a stop portion 94I extending froman end portion on the another side in circumferential direction of theconnecting portion 94H (the second extension portion E2) toward the oneside in the axial direction. The stop portion 94I is stopped at acircular shaped stop hole 30B, serving as a stopping portion, formed inthe base lock 30. Note that the stop hole 30B is illustrated by adouble-dotted dashed line in FIG. 13 to FIG. 17. As illustrated in FIG.13, in a state in which the spool assembly body 80 has been assembled,the stop portion 94I is disposed at a central portion of the stop hole30B in a state not abutting an edge of the stop hole 30B. Then, asillustrated in FIG. 14, when the spool 14 is rotated in the pull-outdirection with respect to the base lock 30 (see FIG. 2 also), the stopportion 94I is abutted by the edge of the stop hole 30B. Displacement ofthe trigger ring 94 toward the one side in the circumferential directionwith respect to the base lock 30 is thereby restricted. When the spool14 is further rotated in the pull-out direction with respect to the baselock 30, the spool 14 is rotated (displaced) toward the one side in thecircumferential direction with respect to the trigger ring 94 (thetrigger ring 94 is displaced toward the another side in thecircumferential direction with respect to the spool 14). Thus, asillustrated in FIG. 15, the restricting portion 94F of the trigger ring94 is disposed (shifted) from the restricting position B1 to thepermitting position B2, and, as illustrated in FIG. 16, the auxiliaryengagement tooth 92B (G2) of the pawl 92 abuts the pawl abut portion 94Gof the trigger ring 94, and is then moved along the pawl abut portion94G. As illustrated in FIG. 17, the pawl 92 is disposed (shifted) fromthe housed position K1 to the engaged position K2, so the engagementteeth 92B of the pawl 92 engage with the engagement tooth portions 48Aof the winding ring 48 as a result. Rotation force of the spool 14 isthereby transmitted to the winding ring 48, and the winding ring 48 isrotated in the pull-out direction together with the spool 14.

When the restricting portion 94F of the trigger ring 94 is disposed inthe permitting position B2, the connecting portion 94H (the firstextension portion E1) of the trigger ring 94 is abutted by the abuttingportion 90F of the connecting portion-placement recessed portion 90E(see FIG. 2). Displacement of the trigger ring 94 toward the anotherside in the circumferential direction with respect to the spool 14 isthereby restricted. When the spool 14 is rotated in the pull-outdirection together with the trigger ring 94 in a state in which theconnecting portion 94H (the first extension portion E1) of the triggerring 94 is abutted by the abutting portion 90F of the connectingportion-placement recessed portion 90E, the stop portion 94I of thetrigger ring 94 is deformed and comes away from the stop hole 30Bprovided in the base lock 30.

Operation and Advantageous Effects of Present Exemplary Embodiment

Explanation follows regarding operation and advantageous effects of thepresent exemplary embodiment.

As illustrated in FIG. 1, in the present exemplary embodiment, thewebbing 100 is worn on the body of a vehicle occupant by pulling out thewebbing 100 from the spool 14.

When the lock mechanism is actuated due to the vehicle colliding in astate in which the webbing 100 is worn on the body of the vehicleoccupant, rotation of the base lock 30 in the pull-out direction isprevented. Rotation in the pull-out direction of the spool 14 that iscoupled to the base lock 30 through the torsion shaft 18 is accordinglylimited, and the webbing 100 is limited from being pulled out of thespool 14. The body of the occupant attempting to move toward the vehiclefront is thereby restrained by the webbing 100.

When the gas generator 42 is actuated due to the vehicle colliding, thenon-illustrated rack is moved, and the pinion gear 88 that meshes withthe rack is rotated in the take-up direction. The spool 14 is therebyrotated in the take-up direction. Thus, a specific length of the webbing100 is taken up onto the spool 14, slack of the webbing 100 worn by theoccupant is eliminated, and restraint force for the occupant by thewebbing 100 is increased.

When, in a state in which rotation of the base lock 30 in the pull-outdirection has been restricted, the body of the occupant pulls thewebbing 100 with an even greater force, and the rotation force of thespool 14 in the pull-out direction based on this pulling force exceeds atwisting withstand load (deformation withstand load) of the twistingportion 18A of the torsion shaft 18 (see FIG. 2), the twisting portion18A is twisted (deformed). Namely, the first force limiter mechanism 16is actuated. Thus, rotation in the pull-out direction is permitted atthe force limiter load of the spool 14 (the twisting withstand load ofthe twisting portion 18A) or greater. Rotation of the spool 14 in thepull-out direction is thereby permitted by the twisting of the twistingportion 18A, and load (burden) on the chest of the occupant due to thewebbing 100 is alleviated due to the webbing 100 being permitted to bepulled out from the spool 14. Kinetic energy of the occupant, providedinto pull on the webbing 100, is absorbed by the amount that thetwisting portion 18A is twisted.

As illustrated in FIG. 4 and FIG. 6, in a state in which the largediameter portion 56C of the cam body portion 56B and the movementportion 54C of the lever 54 abut each other due to the webbing 100 beingworn by an occupant with a large build, the movement portion 54C of thelever 54 is disposed close to the guide face 52D of the wire guide 52.Thus, the energy absorbing wire 50 is sandwiched between the movementportion 54C and the wire guide 52 and is deformed into a substantiallywaved shape along the guide face 52D of the wire guide 52.

As illustrated in FIG. 11 and FIG. 17, when the spool 14 starts to berotated in the pull-out direction with respect to the base lock 30,namely, when the torsion shaft 18 starts to be twisted, the rotationforce transmitting mechanism 82 previously described is actuated, andthe engagement teeth 92B of the pawl 92 engage with the engagement toothportions 48A of the winding ring 48. The spool 14 and the winding ring48 are thereby integrally rotated in the pull-out direction. Asillustrated in FIG. 6, when the winding ring 48 is rotated, the energyabsorbing wire 50 is pulled out from between the movement portion 54Cand the wire guide 52 while being deformed between the movement portion54C and the wire guide 52, and, as illustrated in FIG. 9, the energyabsorbing wire 50 is wound onto the winding ring 48. Thus, rotation inthe pull-out direction is permitted at the force limiter load of thespool 14 (the total of the twisting withstand load of the twistingportion 18A of the torsion shaft 18 and deforming (drawing) load of theenergy absorbing wire 50) or greater.

Thus, the twisting portion 18A of the torsion shaft 18 is twisted andthe energy absorbing wire 50 is pulled out from between the movementportion 54C and the wire guide 52 while being deformed, therebyalleviating the load (burden) on the chest of the occupant due to thewebbing 100, and also absorbing kinetic energy of the occupant, providedinto pull on the webbing 100, by the amount of twisting deformation ofthe twisting portion 18A of the torsion shaft 18 and the amount ofdeformation of the energy absorbing wire 50.

As illustrated in FIG. 7, in a state in which the small diameter portion56D of the cam body portion 56B and the movement portion 54C of thelever 54 abut each other due to the webbing 100 being worn by anoccupant with a small build, the movement portion 54C of the lever 54 isdisposed separated from the guide face 52D of the wire guide 52. Thus, astate arises in which the energy absorbing wire 50 is not deformed, oris barely deformed, between the movement portion 54C and the wire guide52. Thus, when the spool 14 is rotated in the pull-out directiontogether with the winding ring 48, the energy absorbing wire 50 is takenup onto the winding ring 48 without being deformed (or is barelydeformed) between the movement portion 54C and the wire guide 52. Thus,rotation in the pull-out direction is permitted at the force limiterload of the spool 14 (the twisting withstand load of the twistingportion 18A of the torsion shaft 18) or greater.

As explained above, in the present exemplary embodiment, in a case inwhich the webbing 100 is worn by an occupant with a large build, theload value of the force limiter load is a high load value. However, in acase in which the webbing 100 is worn by an occupant with a small build,the load value of the force limiter load is a low load value. Thisenables the occupant to be appropriately protected according to theirphysique.

Note that in the present exemplary embodiment, as illustrated in FIG. 2and FIG. 13, the restricting portion 94F of the trigger ring 94restricts tilting (swinging) of the pawl 92 in a state prior to thespool 14 being rotated with respect to the base lock 30. Namely, thepawl 92 does not engage with the winding ring 48 in a state prior to thespool 14 being rotated with respect to the base lock 30. Thus, thepresent exemplary embodiment enables rotation force of the spool 14 tobe suppressed from being transmitted to the winding ring 48 in a case oftransmitting being not required.

In the present exemplary embodiment, the dimension in thecircumferential direction of the sloped (curved) end T1 of therestricting portion 94F of the trigger ring 94, the end T1 beingdisposed facing the plural engagement tooth portions 48A of the windingring 48 in the radial direction, is set at a dimension that exceeds thepitch between the plural engagement tooth portions 48A of the windingring 48. Thus, when the spool 14 is rotated in the pull-out directionwith respect to the trigger ring 94, the sloped (curved) end T1 spansover two tooth tips 48D provided to adjacent engagement tooth portions48A. This enables the end T1 of the restricting portion 94F of thetrigger ring 94 to be suppressed from engaging unintentionally with theplural engagement tooth portions 48A of the winding ring 48.

In the present exemplary embodiment, in the state prior to the spool 14rotating with respect to the base lock 30, the tooth tip of the mainengagement tooth 92B (G1) of the pawl 92 is positioned slightly furthertoward the radial direction outside than the trigger ring attachmentsection 90A, such that the restricting portion 94F of the trigger ring94 presses the tooth tip of the main engagement tooth 92B (G1) of thepawl 92 toward the radial direction inside. This enables the pawl 92that is rotated together with the spool 14 to be suppressed fromvibrating inside the pawl housing hole 90C, both when the webbing 100 ispulled out from the spool 14, and when the webbing 100 is taken up ontothe spool 14.

In the present exemplary embodiment, the stop portion 94I of the triggerring 94 is stopped at the stop hole 30B of the base lock 30, therebyrestricting displacement of the trigger ring 94 in the circumferentialdirection with respect to the base lock 30. This enables the restrictingportion 94F of the trigger ring 94 to be shifted from the restrictingposition B1 to being disposed in the permitting position B2 and enablesthe pawl 92 to be tilted (swung) to the engaged position K2 by rotatingthe spool 14 in the pull-out direction with respect to the base lock 30,without separately providing a mechanism that shifts the restrictingportion 94F of the trigger ring 94 from the restricting position B1 tobeing disposed in the permitting position B2.

In the present exemplary embodiment, the connecting portion 94H of thetrigger ring 94 is disposed between the connecting portion-placementrecessed portion 90E formed in the pawl housing section 90, and the baselock 30, such that movement of the connecting portion 94H in the axialdirection is restricted. Forming the stop portion 94I so as to extendout from the connecting portion 94H toward the base lock 30 side enablesthe stop portion 94I of the trigger ring 94 to be suppressed fromunexpectedly coming away from the stop hole 30B of the base lock 30.

In the present exemplary embodiment, when the spool 14 is rotated in thepull-out direction together with the trigger ring 94 in a state in whichthe connecting portion 94H (the first extension portion E1) of thetrigger ring 94 is abutted by the abutting portion 90F of the connectingportion-placement recessed portion 90E, the stop portion 94I of thetrigger ring 94 is deformed and comes away from the stop hole 30Bprovided in the base lock 30. This enables the limit on rotation of thespool 14 in the pull-out direction with respect to the base lock 30 bythe trigger ring 94 to be suppressed. Namely, pull-out load of thewebbing 100 from the spool 14 can be suppressed from becoming anunintentional load.

In the present exemplary embodiment, the wound section 94A of thetrigger ring 94 is attached to the trigger ring attachment section 90Aof the spool 14, and the wound section 94A of the trigger ring 94 isformed in a plate shape with its thickness direction in the radialdirection. This enables the wound section 94A of the trigger ring 94 tobe suppressed from projecting out toward the rotation radial directionoutside with respect to the trigger ring attachment section 90A of thespool 14. This enables an increase in the size of the body of thewebbing take-up device 10 to be suppressed.

In the present exemplary embodiment, in a state prior to the woundsection 94A of the trigger ring 94 being attached to the trigger ringattachment section 90A of the pawl housing section 90, the internaldiameter D1 of the wound section 94A is set so as to be smaller than theexternal diameter D2 of the trigger ring attachment section 90A. Thus,the wound section 94A of the trigger ring 94 is expanded in diameter forattachment to the trigger ring attachment section 90A, such that thewound section 94A is wound onto the trigger ring attachment section 90Aby spring force. Thus the attachment work can be simplified, and thewound section 94A is stably retained at the trigger ring attachmentsection 90A due to the spring force.

In the present exemplary embodiment, the end portion 94D on the onecircumferential direction side and the end portion 94E on the anothercircumferential direction side of the wound section 94A of the triggerring 94 overlap each other, and the end portion 94E on the anothercircumferential direction side of the wound section 94A is disposedfurther toward the radial direction outside than the end portion 94D onthe one circumferential direction side thereof. Thus, even though thewound section 94A of the trigger ring 94 has expanded in diameter whenthe spool 14 is rotated in the pull-out direction, the end portion onthe pull-out direction side (the end portion 94D on the onecircumferential direction side) of the wound section 94A of the triggerring 94 can be suppressed from catching on the engagement tooth portions48A of the winding ring 48.

In the present exemplary embodiment, the wound section 94A of thetrigger ring 94 is disposed at the spool 14 radial direction inside withrespect to the winding ring 48, and a dimension (circumferentialdirection length) from the end 94B on the one circumferential directionside of the wound section 94A to the end 94C on the anothercircumferential direction side thereof is set longer than the innerperipheral length (in the circumferential direction) of the winding ring48 (the circumferential length of a circle passing through the teethtips of the engagement tooth portions 48A in axial direction view).Thus, even though the wound section 94A of the trigger ring 94 hasexpanded in diameter when the spool 14 is rotated in the pull-outdirection, the end portion on the pull-out direction side (the endportion 94D on the one circumferential direction side) of the woundsection 94A of the trigger ring 94 can be prevented from being exposedto the outer periphery of the wound section 94A and from catching on theengagement tooth portions 48A of the winding ring 48. This enablesrotation force of the spool 14 to be prevented from being transmitted tothe winding ring 48 through the trigger ring 94.

In the present exemplary embodiment, as illustrated in FIG. 15 to FIG.17, when the pawl 92 is pressed back toward the opposite side to theengaged position K2 side in the process in which the pawl 92 isdisplaced toward the engaged position K2 side, the pawl abut portion 94Gof the trigger ring 94 is deformed toward the opposite side to the pawl92. Note that the pawl abut portion 94G that has been deformed towardthe opposite side to the pawl 92 is capable of returning toward the pawl92 side. This enables the pawl 92 that has been pressed back toward theopposite side to the engaged position K2 to be urged toward the engagedposition K2 side.

In the present exemplary embodiment, the pawl 92 is disposed on theradial direction inside with respect to the wound section 94A of thetrigger ring 94, and the pawl abut portion 94G which is abutted by thepawl 92 extends toward the radial direction inside of the wound section94A. This enables the rotation force transmitting mechanism 82 thattransmits rotation force of the spool 14 to the winding ring 48 to besuppressed from increasing in size in the rotation radial direction ofthe spool 14.

Rotation Force Transmitting Mechanism According to a Second ExemplaryEmbodiment

Explanation follows regarding a rotation force transmitting mechanism 82according to a second exemplary embodiment, with reference to FIGS. 18Ato 18E. Note that members and sections corresponding to the aboveexemplary embodiment are appended with the same reference numerals asthose in the above exemplary embodiment, and explanation regarding thesemembers and sections is sometimes omitted.

As illustrated in FIGS. 18A to 18E, in the rotation force transmittingmechanism 82 of the present exemplary embodiment, a width W1 of aportion of the wound section 94A of the trigger ring 94 where the pawlabut portion 94G and the restricting portion 94F are not provided is setnarrower than a width W2 of a portion of the wound section 94A where thepawl abut portion 94G and the restricting portion 94F are provided. Thisconfiguration enables the force required to expand the diameter of thewound section 94A of the trigger ring 94 to be reduced. Thus, thepresent embodiment enables excellent ease of assembly when attaching thewound section 94A of the trigger ring 94 to the trigger ring attachmentsection 90A of the pawl housing section 90.

Rotation Force Transmitting Mechanism According to a Third ExemplaryEmbodiment

Explanation follows regarding a rotation force transmitting mechanism 82according to a third exemplary embodiment, with reference to FIG. 19 toFIG. 21. Note that members and sections corresponding to the aboveexemplary embodiments are appended with the same reference numerals asthose in the above exemplary embodiments, and explanation regardingthese members and sections is sometimes omitted.

As illustrated in FIG. 19, in the rotation force transmitting mechanism82 of the present embodiment, a restricting portion 94F formed insubstantially an L shape is provided at the end portion 94D on the oneside in the circumferential direction of the wound section 94A of thetrigger ring 94, and a pawl abut portion 94G is provided at the endportion 94E on the another side in the circumferential direction of thewound section 94A. In the present embodiment, a restricting portionplacement groove 90G, in which an end portion T2 on the one side in theaxial direction of the restricting portion 94F of the trigger ring 94 isdisposed, is integrally formed in the pawl housing hole 90C. Asillustrated in FIG. 20, the restricting portion 94F of the trigger ring94 abuts the radial direction outside face (the face where the raisedportion 92C (see FIG. 13) is formed) of the pawl 92, such that tilting(swinging) of the pawl 92 is restricted.

As illustrated in FIG. 21, when the spool 14 is rotated in the pull-outdirection with respect to the trigger ring 94, a portion (the endportion T2 on the one side in the axial direction) of the restrictingportion 94F of the trigger ring 94, that is stopped at the restrictingportion placement groove 90G, is deformed, and a state arises in whichthis portion does not abut the radial direction outside face of the pawl92 (the restricting portion 94F of the trigger ring 94 is disposed inthe permitting position B2). Then, the pawl 92 is tilted (swung) alongthe pawl abut portion 94G of the trigger ring 94, thereby enabling thepawl 92 to engage with the winding ring 48 (see FIG. 3).

Rotation Force Transmitting Mechanism According to a Fourth ExemplaryEmbodiment

Explanation follows regarding a rotation force transmitting mechanism 82according to a fourth exemplary embodiment, with reference to FIG. 22and FIG. 23. Note that members and sections corresponding to the aboveexemplary embodiments are appended with the same reference numerals asthose in the above exemplary embodiments, and explanation regardingthese members and sections is sometimes omitted.

As illustrated in FIG. 22, the rotation force transmitting mechanism 82of the present embodiment has features of including a trigger piece 96serving as a restricting member, and of being configured including anon-illustrated spring that urges the pawl 92 in a direction tilted(swung) in the arrow Y2 direction. Note that a stopping portion 30C atwhich the stop portion 94I of the trigger piece 96 is stopped is formedin the base lock 30.

As illustrated in FIG. 22 and FIG. 23, in the present embodimentexplained above, the restricting portion 94F of the trigger piece 96 isdispose (shifted) from the restricting position B1 to the permittingposition B2 when the spool 14 is rotated in the pull-out direction withrespect to the base lock 30. When the restricting portion 94F of thetrigger piece 96 is shifted from the restricting position B1 to beingdisposed in the permitting position B2, the pawl 92 is tilted (swung) inthe arrow Y2 direction due to the urging force of the non-illustratedspring. Thus, the pawl 92 engages with the winding ring 48 (see FIG. 3),and rotation force of the spool 14 is transmitted to the winding ring48.

Note that in the present embodiment, an example has been explained inwhich a non-illustrated spring is provided; however, configuration maybe such that the spring is not provided. In such a case, configurationmay be such that the pawl 92 is tilted (swung) in the arrow Y2 directionunder centrifugal force arising in the pawl 92 due to the pawl 92 beingrotated together with the spool 14.

In the above exemplary embodiments, an example has been explainedconfigured such that rotation force of the spool 14 is transmitted tothe winding ring 48 by actuating the rotation force transmittingmechanism 82; however, the present disclosure is not limited thereto.For example, configuration may be such that rotation force of the spool14 is transmitted to the frame 12 by actuating the rotation forcetransmitting mechanism 82 when the spool 14 has rotated a specificnumber of times with respect to the base lock 30. In such aconfiguration, the pawl 92 engages with the frame 12 when the spool 14has rotated the specific number of times with respect to the base lock30. This enables rotation of the spool 14 in the pull-out direction tobe limited.

In the above exemplary embodiments, an example has been explained inwhich the trigger ring 94 and the trigger piece 96 are each formed usinga single plate shaped member; however, the present disclosure is notlimited thereto. For example, the trigger ring 94 and the trigger piece96 may each be formed using a wire shaped member.

As illustrated in FIG. 5 to FIG. 7, in the above exemplary embodiments,an example has been explained configured such that switching, betweenwhether or not the energy absorbing wire 50 is deformed between themovement portion 54C of the lever 54 and the wire guide 52, is performedby providing the cam turning mechanism 58; however, the presentdisclosure is not limited thereto. For example, configuration may besuch that an actuator actuated when the webbing 100 is worn by anoccupant with a large build is provided, and the movement portion 54C ofthe lever 54 moves toward the wire guide 52 side when the actuator isactuated.

Exemplary embodiments have been explained above. However, it is notlimited to the above description, and obviously various othermodifications may be implemented within a scape not departing from thespirit of the present invention.

What is claimed is:
 1. A webbing take-up device comprising: a spool thattakes up a webbing worn by an occupant, and that is rotated in apull-out direction due to the webbing being pulled out; a lock sectionthat is configured to rotate integrally with the spool, and that isrestricted from rotating in the pull-out direction in a vehicleemergency so as to limit rotation of the spool in the pull-outdirection, with respect to the lock section; a pawl that is rotatedtogether with the spool and that, by being displaced, engages with arotation force transmitting member so as to transmit rotation force ofthe spool to the rotation force transmitting member; and a restrictingmember that includes a restricting portion, wherein the restrictingportion is disposed in a restricting position between the pawl and therotation force transmitting member, at which displacement of the pawl isrestricted, in a state prior to the spool being rotated in the pull-outdirection, with respect to the lock section, and the restricting portionis disposed in a permitting position at which displacement of the pawlis permitted in a case in which the spool is rotated in the pull-outdirection, with respect to the lock section, wherein the restrictingmember is configured including a stop portion that restrictsdisplacement of the restricting member in a rotation circumferentialdirection of the spool, with respect to the lock section, by beingstopped at a stopping portion formed at the lock section.
 2. The webbingtake-up device of claim 1, wherein: a plurality of engagement toothportions with which the pawl is engaged are provided at the rotationforce transmitting member; and a dimension, in a rotationcircumferential direction of the spool, of an end of the restrictingportion, the end being disposed facing the plurality of engagement toothportions, exceeds a pitch between the plurality of engagement toothportions.
 3. The webbing take-up device of claim 2, wherein therestricting portion presses the pawl in the state prior to the spoolbeing rotated in the pull-out direction, with respect to the locksection.
 4. The webbing take-up device of claim 2, wherein: therestricting member is configured including a wound section that isattached to a ring shaped restricting member winding section provided atthe spool, the wound section being formed in a ring shape correspondingto the restricting member winding section, and the wound section beingformed in a plate shape with a thickness direction thereof being arotation radial direction of the spool.
 5. The webbing take-up device ofclaim 4, wherein: a first end portion on a pull-out direction side ofthe wound section and a second end portion on an opposite side to thepull-out direction side of the wound section overlap with each other;and the second end portion is disposed further toward an outer side inthe rotation radial direction of the spool than the first end portion.6. The webbing take-up device of claim 1, wherein the restrictingportion presses the pawl in the state prior to the spool being rotatedin the pull-out direction, with respect to the lock section.
 7. Thewebbing take-up device of claim 1, wherein: the restricting member isconfigured including a facing portion, the facing portion beingrestricted from moving in a rotation axis direction of the spool bybeing disposed between the lock section and the spool; and the stopportion extends from the facing portion.
 8. The webbing take-up deviceof claim 7, wherein: the restricting member is configured including anabut portion that restricts displacement of the restricting member, withrespect to the spool, by being abutted by an abutting portion providedat the spool in a case in which the restricting portion is disposed inthe permitting position; and after the abut portion is abutted by theabutting portion, the stop portion comes away from the stopping portionin a case in which the spool is rotated in the pull-out direction, withrespect to the lock section.
 9. The webbing take-up device of claim 1,wherein: the restricting member is configured including an abut portionthat restricts displacement of the restricting member, with respect tothe spool, by being abutted by an abutting portion provided at the spoolin a case in which the restricting portion is disposed in the permittingposition; and after the abut portion is abutted by the abutting portion,the stop portion comes away from the stopping portion in a case in whichthe spool is rotated in the pull-out direction, with respect to the locksection.
 10. The webbing take-up device of claim 1, wherein: therestricting member is configured including a wound section that isattached to a ring shaped restricting member winding section provided atthe spool, the wound section being formed in a ring shape correspondingto the restricting member winding section, and the wound section beingformed in a plate shape with a thickness direction thereof being arotation radial direction of the spool.
 11. The webbing take-up deviceof claim 10, wherein: a first end portion on a pull-out direction sideof the wound section and a second end portion on an opposite side to thepull-out direction side of the wound section overlap with each other;and the second end portion is disposed further toward an outer side inthe rotation radial direction of the spool than the first end portion.12. The webbing take-up device of claim 11, wherein: the wound sectionis disposed at an inner side in the rotation radial direction of thespool with respect to the rotation force transmitting member that has aninner peripheral portion formed in a ring shape; and a length from oneside end in the rotation circumferential direction of the spool toanother side end in the rotation circumferential direction of the spoolof the wound section is longer than an inner peripheral length in therotation circumferential direction of the spool of the rotation forcetransmitting member.
 13. The webbing take-up device of claim 10,wherein: the wound section is disposed at an inner side in the rotationradial direction of the spool with respect to the rotation forcetransmitting member that has an inner peripheral portion formed in aring shape; and a length from one side end in the rotationcircumferential direction of the spool to another side end in therotation circumferential direction of the spool of the wound section islonger than an inner peripheral length in the rotation circumferentialdirection of the spool of the rotation force transmitting member.